Combustion of fuels



ratios commonly employed which of the of chlorine will be required for fuels of different 15 'Patentecl June 11, 1940 v I UNITED STATES PATENT 'OFFICE' COMBUSTION F FUELS George B. Murphy and William H. Hubner, Chicago; 111., assignors to Universal Oil Products Company, Chicago, 111., a corporation of Delaware No Drawing. Application September 27, 1937, Serial No. 165,942

4 Claims. (01. 123-1) .This invention relates more specifically to the sult to find that regulated chlorine injection combustion of hydrocarbon fuels in comprestended to increase knocking. sion ignition engines. Probably the simplest method of operating In a more specific sense it is concerned with Diesel engines in accordance with the present inmethod of injecting combustion accelerators into Vention is to maintain a ep cylinder of 5 the air entering the cylinders of compression ignicflmpressfid chlorine. e y d being pp tion engines of the Diesel type to facilitate easier with a control valve set to deliver regulated startin nd reduce t ignition-1agf or amounts of the gas to the air intake. However, angle. it is comprised within the scope of the invention In internal combustion engines which depend to employ any device or method which will assure upon t heat generated by compression for the the regulated admission of the proper quantities ignition of the injected fueLit is known that the the F 001% any defects n the ignimost reliable fuels in regard to ease of ignition tion or combustion of whatever fuel may be used. and smooth burning under the compression It 18 more or less apparent that difierent amounts proximate order of from 10:1 to 20:1, are those mi composition and combustion. charm of a paramnic character which evidently crack teristics and that the necessary quantities will more easily than corresponding f-uels containing vary wlth such Factors as the compression hydrocarbons of a cyclic character so that active ratio speed the engltle and other factors radicals are formed which unite readily with the extenswe expenments have that oxygen in the injected air and instigate the comchlorme m be employed as cmpbusfimn accelbustion reactions. This requirement of paraflierator wlth any fombmatmn of fuel nicity to insure combustion characteristics elimand ignitmn f inates the majority of cracked distillates as a The followmg data E mtrqduced tqshow the source of Diesel fuel at least for light Diesel enf f p the operatwn 9 Dlesel engmes when gines and has resulted in considerable experimenp q f quantifies of chlorm? into the tation with the object of rendering such distilan Whfle the data are typical they lates usab1e are not introduced for the purpose of unduly Along the line of improving Diesel operation, a hmltmg the siwpe of the mYention smce other large number of so-called dopes or accelerators types 9 fuels m different engmes would respond have been tried which are added in small quantity to dlfierent extent to the fuel, most of these being oxidized com- :rests were run on stindard Dlese] test engine Pounds of the character of nitrates or other ex- Straight run Dlese]. fuel y mlxe-d v pOsive ,materiala The present invention base crude and a corresponding fraction from the preaches the problem from a somewhat different cracking of the heavier fractions of the Same angle. crude oil. while operating under standard con- I one specific embodiment the present ditions, the amount of chlorine fed to the air invention comprises the injection of controlled take by Weight of the fuel. was Varied and e amounts of chlorine into the air stream passing pr vement in cetane number (which measures 40 to the cylinders of compression ignition engines the value of Diesel fuels) was noted. The followto increase the ease of ignition and smoothness ihg table Shows e esu s edof burning of the fuels.

It is not intended to advance. an exact mecha- Straight Diesel fuel nism for explaining the observed results of chlorine injection. alth u h the su gestion may be tfi'fiittffiitlifni fiflittz1:::312311331321: c3 6 9 13 1 1 made that the effect is catalytic with the formation of intermediate addition compounds between cracked Diesel fuel the-unsaturated radicals and chlorine. The fact that c o ne could be used as a combustion accel- Percent chlorine added 0 I 3 5 5o erator was not predictable since there 15 consid- Equivalent octane number 49 60 64 69 erable evidence in support of opposite predic-i tions. Many chlorine compounds such as, for It will be seen from the above data that the example, carbon tetrachloride, are retarders of maximum effect of the chlorine occurred in the combustion and it was a new and unexpected recase of the cracked fuel which is of obvious advantage since an invention of the present character is most needed to improve the combustion properties of cracked distillates;

We claim as our invention:

1. The method of increasing the knock value of Diesel fuels in acompression ignition engine which comprises introducing free chlorine thereto through the air-intake of said engine to accelerate combustion of the Diesel fuel.

2. The method of increasing the knock value of hydrocarbon Diesel fuels of low paraflinicity when I used in a compression ignition engine, which com- 3. In the operation of compression ignition engines operating upon hydrocarbon Diesel fuels, the method of improving the operation of the engine which comprises adding free chlorine to the air supply for the engine to accelerate combustionof the Diesel fuel.

4. In the operation of compression ignition engines operating upon hydrocarbon Diesel fuels, the method of improvingthe operation of the engine which comprises adding to the air supply for the engine, as a combustion accelerator for the Diesel fuel, an amount of free chlorine equal to about 1-5% of the fuel.

a GEORGE B. MURPHY.

WILLIAM H. HUBNER. 

